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Comment by hellbanner | Hacker News Reader

Houston has their downtown lights turn green sequentially if you travel the speed limit. Nifty: http://www.houstonchronicle.com/news/houston-texas/houston/a...

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Yep, known as the Green wave: https://en.wikipedia.org/wiki/Green_wave

If you think about it for a second, it's only really possible to do this for one direction of traffic at a time on a given multi-block street segment.

(Haven't read the article yet, but) I guess they could have it set up for rush hour, and the streets going in and out of downtown generally have one large street with only smaller streets (many of them with only stop signs) going perpendicular.

Good thing the streets are all one-way!

Seriously though, in the downtown portion of Houston there are only two directions people want to go in a hurry, northeast and southwest. Those roads have at least double the carrying capacity of the cross-roads and as such it absolutely makes sense to optimize the lights for them.

So what happens is that the "get me out of downtown" roads are very well timed and the cross-streets aren't but that's OK. Most people don't need the cross-streets and if they do, they're fairly lightly traveled because most people don't need them.

As someone who does need to travel on the cross streets fairly often, the downside of this is that the non major streets have lights that are _really_ poorly timed.

I realize why they do it, and it is optimizing for the majority use case, but damn is it annoying when you want to go the other way...

Yeah it's terrible. I do the West End ride sometimes and all down washington it's fine. Then we hit downtown and we get stopped at EVERY light. Once we hit fannin and turn for the med center it's green lights all the way and you see 30-50 cyclists just cruising in an urban environment; it's surreal.

There are places in Milwaukee where it seems that all the lights turn green as you approach them, but unfortunately this is of no use. The cars who have been waiting at the red light take ~30 seconds to get moving again (texting/delayed reaction time/conservative acceleration * 5-6 cars) so you still have to stop, it's just that you're stopping at green lights. Incredibly frustrating.

Hence I'm waiting for self driving electric cars, which can start going almost immediately at a green.

I've heard about this before but never seen it in writing, thanks. It is pretty neat. Do other cities not have the same?

Austin does. Also, feeder roads along highways are a great Texas feature, too.

Apparently[0] the term feeder is almost entirely unique to Houston.

[0] http://www4.uwm.edu/FLL/linguistics/dialect/staticmaps/q_99....

Huh, ever since moving away, I've greatly enjoyed not having access roads. I feel like they greatly encourage a particularly walking-unfriendly sort of suburban sprawl in which there are long rows of large chain stores and restaurants directly facing highways and no opportunity for any sort of neighborhood to exist around them.

They are also very dangerous: they combine people getting off the highway with people accelerating to get on with people entering and leaving those shopping centers and restaurants. It really creates for messy traffic.

Feeder roads are one of the worst features of Texas.

I thought these were called frontage roads? I mean, in Mississippi, they are just called that.

I prefer living in the north where they do not have such monstrosities. But I currently live in Beijing, so I have to deal with the "fulu" all the time.

They exist in the north: http://en.wikipedia.org/wiki/Van_Wyck_Expressway

Wow, I didn't realise that feeder roads were a Texas-specific thing. How do other parts of the country handle commercial properties that face highways?

Other parts of the country call these roads "frontage roads" or "service roads" if they are what I'm thinking of (never been to Texas). They do exist outside of Texas; I've seen them in Myrtle Beach, SC, for instance.

It is bizarre (and a bit frustrating) to drive down a NJ turnpike and miss your exit. You have to drive 15 miles to the next one to turn around. And most urban centers are miles from the exit. No stores around. I like the latter, not so much the former.

Frontage roads take up a lot of space and are not pedestrian-friendly, but they can help drivers. Personally, I'm not a fan of them because I like walkable cities.

Tampa, FL does. I have seen it in several other places, I didn't think it was a novelty.

Its mostly a southern thing. I've never seen it in the north, but it is common in...China around the ring roads.

Valencia Street in SF has this, but it's set for 13mph, for bikers.

Sydney invented a system used by a few countries that optimises traffic lights for public transport. So if a bus is running late, there is a higher chance it will get more green lights.

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